Post any file to Slack. Up to 10 files at once, ~100 MB combined, with caption, in a specific channel or thread. Also supports thread chaining and private file hosting.
This plugin is a small compagnon to Bubble’s official Slack plugin (which doesn’t offer the option to post files or attach them to messages).
We use Slack’s current file upload API (which replaces the deprecated files.upload method since 2025).
The plugin offers two actions:
It talks to Slack directly using your bot token.
You can also use the plugin as per-user private storage: pass a direct-message channel ID instead of a team channel ID and the files are hosted in Slack but visible only to that one user (see the "Hosting files privately" section below).
| Situation | Action |
|---|---|
| Upload a profile photo when a user updates their avatar | Upload a Single File |
| Send a generated invoice PDF when an order is placed | Upload a Single File |
| Email-to-Slack relay (single attachment per email) | Upload a Single File |
| Daily digest with 5 reports for the team | Upload Multiple Files |
| Bulk export, 8 CSVs from a search | Upload Multiple Files |
| End-user multi-file upload form (e.g. drag-drop a folder) | Upload Multiple Files |
| You want one Slack message regardless of file count | Upload Multiple Files (with a 1-item list works fine too) |
| You're not sure how many files you'll have | Upload Multiple Files (handles 1-10 transparently) |
If you only ever upload one file at a time and want the simplest workflow, use Upload a Single File. If you need to batch, use Upload Multiple Files. They share the bot token and channel conventions, so switching between them later is just a different action picker, no Slack-side reconfiguration.